About Fail safe of AM26LV32E

Dear Ron Michallick-san

Thank you for reply.

Is AM26LV32 classified into Transceiver"Z" of the attachment application note?

1033.slyt514.pdf

Consequently, Is VID<=200mV have no problem for the fail-safe of AM26LV32?

Moreover, is fail-safe only short?
(Doesn't it correspond to Open?)

Best regards,

Satoshi

Satoshi-san,

Yes it is like Transceiver "Z". Fail safe for short (port A to B); fail safe for Open (port A and Port B no connection); and Terminated (port A and B only connected to line termination resistor).

Pages 7 through 11 in data sheet have cautions to make sure the fail safe works correctly. 

Dear Ron Michallick-san

Thank you for the advice.

Please let me also know the following by addition.

This time, the client will replace to AM26LV32 at RS-422.

Since the RS-422 device which was being used in the past had not carried out Fail-Safe correspondence, it constituted from external resistance.

Please refer to the berrow.

If client replace to AM26LV32E, which is it better the external resistance keep-attached or remove?

The background, client want to examine what happens to a theoretical output, by the difference of Va～Vb by external resister "attached or nothing". (Usually, short, termination)

- Is it right in the idea that Va～Vb=XX～YY[V] guarantees "H" on each conditions?

- When right, how is the value of XX and YY decided?

Moreover, does the structure of internal FailSafe differ in AM26LV32 and AM26LV32E?

(If the 3rd page of the datasheet is both compared, internal resistance differs)

Best regards,

Satoshi

Satoshi-san,

Do points XX and YY refer to the external device pins?
The AM26LV32E has a better fail safe that is missing the potential issue that the AM26LV32 has.
The external 1k resistors can be present or not. It will work well both ways.

Dear Ron Michallick-san

I appreciate the quick reply.
"XX～YY" is the range of VA～VB, to the inside of a device.
 
・If connect external 1kΩ resister

　⇒Internal and external total.

・If not connect external 1kΩ resister
　⇒nternal only.

Best regards,

Satoshi

Satoshi-san,

TI-Tina (free application) circuit attached. Does this help?

Dear Don Michallick-san

Thank you for many reply.

"–0.2V < Va-b < 0.07V" is indeterminate or logic"H", which does it become?

Since the Tina-TI file (no external register) got the other day will be about Va-Vb=60mv by OPEN, it is set to spec-NG.

Please let me check.

0310.AM26LV32E - autosave 14-06-16 16_34.TSC

And, Is there any data of status according to the range of Va-b?

Example）

・Va-b ＞ 0.2V 　 　⇒Logic "H"

・0.07V ＜ Va-b ＜ 0.2V 　 　⇒Logic" H"

・-0.2V ＜ Va-b ＜ 0.07V 　 　⇒indeterminate

・Va-b ＜ -0.2V 　 　⇒Logic "L"

Is it right in the above-mentioned idea?

Best regards,

Satoshi

As for the content on which it questioned the other day, how about the situation?

Please teach if there are specs and information for which the confirmation is necessary to answer.

I will confirm it.

Best regards,

Satoshi